Rocker blade bit



y 1 c. E. BANNIS TER 2,002,388

ROCKER BLADE BIT Filed Nov. 14, 1933 3 Sheets-Sheet 2 afforvzq'ys y 1935 c. E. BANNISTER 2,002,388

ROCKER BLADE BIT Filed Nov. 14. 1933 3 Sheets-Sheet 3 u y 129 1 i 131 125 I i J Lil " ,ZZzvazzfioz attorneys Patented May 21, 1935 UNITED STATES PATENT OFFICE 2,002,388 nocxna BLADE nrr Clyde n. Bannister, Akron, Ohio Application November 14, 1933, Serial No. 697,883 I 12 Claims. (01. 255-51) This invention relates to rotative bits and is of especial valuefor earth-boring bits of the oscillatng type. 1

The chief objects of the invention are to provide a bit adapted to cut with high directions of rotation, to

effectiveness in both provide economy ofmanufacture, to provide for convenient and economical repair of a adapted to function effectively for time without repairs and, more specifically,

dulled or broken bit, to provide a bit long periods of sharpening or for to provide a selfinterruption for sharpening bit.

Of the accompanying drawings: Fig. 1 is a side elevation of one embodiment of my invention.

Fig. 2 is a bottom plan view of Fig.3isa

of Fig. 3.-

.Fi 5 is the same.

vertical sectional view on the line aside elevation of another embodiment of my invention.

Fig. 6 is a bottom plan view of the same.

Fig. '7 is a vertical sectional view on the line '|"-'l of Fig. 6.

Fig. 8 is a cross-sectional view on the line 88 of F18. 7. a

Fig. 9 is a bottom plan view of a modification 4 having staggered blades I Fig. 10 is a cross-sectional view illustrating a reversible tapered blade.

Fig. 11 is a cross-sectional view illustrating'a toothed blade, the blade-holding recess having provision to permit rocking blade therein.

or pivoting of said Fig. 12 is-a perspectiveview of the toothed blade illustrated in section in Fig. 11.

Fig. 13 is an elevation'of a bit. equipped with blades such as that of Figs. 11 and 12.

Fig. 14 is a vertical section of the same.

Referring now description of to the drawings for a particular my invention, I designates generthreaded portion 3 adaptedfor attachment to and detachment from a suitable spindle or check. This bit i has a conical portion 4 terminating in a point 5.

bit i.

The groove Mounted within the conical portion 4 of these blades of the recess said shaft seatlli at one endof the groove 6 and 8 is flared at its lower end as at It,

,most efilcient cutting bladesand of the bore in V thickness 6'. A shaft 9 passes blade I is free to rock or pivot on the shaft 9 within the limits permitted by the walls of the groove 6 and the flared walls l2.

Each shaft 9 has a projecting end l6, and through this projecting end It and into the bit I is threaded 'a screw II or other retaining element to prevent endwise movement of the shaft 9 until it is desired to remove the same.

Each blade 'I is provided with two cutting edges, l4 and i5, Thus when the bit is oscillated to the left, Fig. 1, the cutting edge ll will be presented to the formation being cut, and the blade I will rock or pivot on the shaft 9 until the cutting edge I4 is presented to the formation to be cut at the angle. when the bit i oscillates in the opposite direction, or to the right),

Fig. 1, the cutting edge li will be presented to the formation being cut, and the blade 1 will again rock or pivot on the shaft 9 until the blade I5 is presented at the best and most eflicient cutting angle. Thus two separate anddistinct cutting edges are provided on each blade, doubling the life and efliciency of these blades and increasing the speed of the work accomplished.

When it is desired to remove a blade 1 because of wear,.breakage, or for other reasons, the screw I1 is removed, the shaft 8 withdrawn from the recess l0, through the blade I, and aperture H, whereupon the blade I will drop from its groove 6 and may be readily replaced with another blade, the shaft 9 then being replaced through the recess I, new blade I, and into the recess i0, whereupon the screw I1 is replaced and the bit is again ready for operation. This is a simple procedure and requires but a short space of time to efiect these changes.

In order to provide for suitable flushing of the which they are operatmg, I form my novel bit partially hollow, as illustrated at l8, and through the solidportion of the bit vI form fluid conducting apertures l9,

three of these apertures being illustrated herein, although it will be appreciated that I mayv utilize any desirable number of same. The outlets of these apertures are preferably located closely adjacent to the blades 1 in order to insure that the blades will be kept well flushed, as well as flushing the cuttings of the blade from the bore in which they are operating. 1 Each of the blades is inclined, because of the conical portion 4 of the bit I,- and each blade is angularly disposed with relation to the adjacent blades. Thus an extremely efiicient type of bit is produced, particularly. adapted for cutting through hard formations.

It will thus be instantly apparent to thoseskilled in this art that I have devised an entirely novel bit, one having great efliciency and possessing many advantageous features not heretofore found in existing bits. Each blade 'I projects beyond the periphery of the bit I, thus insuring a complete cutting of the bore without offering any resistance to the downward passage of the bit as it follows the blades in their downward path in the bore-cutting operation.

Each blade I is slightly V-shaped, as clearly illustrated, to provide the cutting edges I4 and I5. These blades 1 are easily re-sharpened and will have long life due to their novel and rugged structure.

The threaded portion 3 will, of course, be locked to the corresponding threaded portion of the spindle to which the bit is attached, thus preventing twisting oil of the bit from the spindle during oscillatory movement of the bit. This locking can be efiected in any desirable, suitable, or convenient manner.

Referring now to the embodiment shown in Figs. 5, 6, 7 and 8, I M designates generally a bit having a reduced and threaded neck I02 and a conical head I03. Arranged at predetermined intervals around theperiphery of the bit IOI are a plurality of vertical ribs I04. lhclined recesses I05 are provided extending through the ribs I04, partially through the bit IOI and to the center of the head I03. Positioned in each of these recesses I05 is a cutting element or blade I06 having a cutting portion I01 and a cutting portion I08, each portion I01 and I08 being provided with a plurality of cutting edges. These blades I06 are removably attached to the bit by rivets I09, one of said rivets extending through each rib I04. Flushing fluid exhaust outlets IIO are provided extending through the bit and terminating in the conical heads I03, each of said outlets being positioned between two of the cutting blades, although this arrangement and number of fluid outlets is optional.

Because of the reversability of the blades I06, when one portion, such as I01 for example, has become dulled through use, or has beenbroken and it is desired to reverse the blade, it is a simple matter to remove the rivets or bolts I09, withdraw the blades I06, reverse the same so'that anew cutting portion, such as posed or cutting position, bolts I09, and the tion.

Each blade I06 is inclined, and is angularly disposed with relation to the other blades of the bit, and each blade I06 extends beyond the 'outer edge 'of the ribs I04 so'that the blades will cut I08, will be in exreplace the rfvets or bit is again ready for operaa bore of greater diameter than the diameter of the bit. Thus the bit will meet with no resistance by the walls of the bore in its downward passage.

The blades I06 are not only removableand reversible, but are also interchangeable with any of the other blades in a bit, or with the blades in other bits.

This novel bit is possessed of many advantageous. features, such as strength, durability, ruggedness, efficiency, quick-cutting capacity, length j of life,

as well as the reversability and interchangeability above briefly described.

is provided which acts as a pivot.

posed portion I2l of wear or its-bevel In Fig. 9 1 have illustrated 'a modification II2 hasa conical head H3 and the recesses or grooves II 4 beboth the head H3 and rib II5.

wherein the bit vertical ribs II5, ing provided in These recesses, tioned therein, are staggered and this form or arrangement of blades will be found advantageous in cutting through or boring certain formations. Each blade II5 is fixed to the ribs II5 and bit II2 by rivets or bolts II'I.

Flushing fluid exhaust outlets IIB are provided for flushing the blades and for flushing the cuttings of the blades out of the bore, the blades II6 being reversible, removable, and interchangeable in the same manner as the blades I06. With these staggered blades, however, they cannot be inserted longitudinally of the grooves, but must be inserated laterally thereof.

as well as the blades II 6 posi- In Fig. 10 I have illustrated another modificamoved or withdrawn longitudinally of the groove I23, instead of merely dropped therefrom as in removing the blade I06. This tapered blade I insures a strong firm holding of the blade in the groove, rivets or bolts being utilized to further insure this holding of the blade.

In Figs. 11, 12, 13 and 14 is illustrated a still further type of reversible blade I25, having tapered cutting portions I26 and I21. A central longitudinal projection I28, preferably rounded,

is adapted to be inserted longitudinally into a groove I33 in the bit I34, this groove being of a size to snugly receive the pivot portion I28 of the blade I',"but the upper and lower portions of the groove I33 being'of a greater size than the portions I 26 and I2! of the blade I25. This per- This blade I25 7 mitsa rocking or pivoting of the blade I25 through a slight angle. Each portion I26- and I 27 is provided with alternately arranged teeth I29, I29, and. I30, I30. The cutting edges I3I of the teeth I29 are all on one side other side, thus afiording two each portion I26 and I21. Thus, when the bit- I34 is oscillated in one direction, the cutting edge on one side of the exthe blade I25 will'dig in, while the other cutting edgewill dig in while the bit is going in the opposite direction, the rocking cutting edges on or pivoting of the blade I 25 presenting these.

cutting edges at the best and most efficient cutting angle. Thisblade I25 is likewise-reversible, removable,- and'interchangeable, thus possessing all of the advantages of the blades above' described. 4

The threaded portion I02 willfof coarsegbe locked to the threadedspindle to which it is'attached. This lockin'g'fmay be efiected inany desired or convenient manner, many methods and means of thread-locking being well-knownand it not being deemed necessary toillustrate the same 7 in the present, application.

This form of bit providesa self-sharpening feature, as adjacent teeth at the leading side of the bit leave between themiz ridge of material in contact with which the intervening, oppositelyfacing tooth is dragged backward, with resulting ting edge.- 1 Various further [modifications are possible or edge, and the cutting edges I32 of the teeth I are all on .the

face and sharpening of its ciitconverging recesses within the scope of my invention as deflned in the appended claims.

I claim:

- A bit of the kind described, having a conical lower portion and having a plurality of inclined formed in the conical portion thereof terminating at a substantially common center, a shaft passing through' each of said recesses, a blade pivotally mounted on each of said shafts, and means to limit the pivotal movement of each blade.

2. A bit of the kind described, having a conical lower portion and having a plurality of converge ing recesses formed in the conical portion thereof terminating at a substantially common center, a shaft passing through each-of said recesses and fixed at one end to said bit, a blade pivotally mounted on each of said shafts, and means to limit the pivotal movement of each blade.

3. A bit of the kind described, having a conical lower portion and having a plurality of converging recesses formed in the conical portion thereof terminating at a substantially common center, a shaft passing through each of said recesses and fixedat one end to said bit, a blade pivotally mounted on each of said shafts, and means to limit the pivotal movement of each blade, said blades having a plurality of cut ing edges.

4. In an oscillating bit of the kind described, a pivoted cutting blade having a plurality of cutting edges adapted to effect an equal cutting action in different directions, oscillation of said bit automatically rocking said blade and presenting one of said cutting edges to the material to be cut, and means to limit the rocking movement of said blade.

5. In a bit of the kind described, a pluralityof inclined divergently located cutting blades, an-

gularly disposed with relation to each other and pivotally mounted on said bit, blade having a plurality of cutting edges adapted to effectan equal cutting action in different directions, and means to limit the pivotal movement of said blades.

6. A bit of the kind described, having a conical lower portion and having a plurality of inclined each of' converging recesses formed in the conical portion thereof and terminating at a substantially common center, a blade pivotally mounted in each of said recesses, each of said blades having a reduced portion housed in its recess within the bit to limit the pivotal movement of the blade.

'7. The combination with a bit of the kind described; of a plurality of reversibleblades, each blade having two cutting portions, and each cutting portion having on one side of the bits axis a plurality of teeth alternately facing in opposite directions.

8. The combination with a bit of the kind described, of a plurality of reversible blades, each blade having two cutting portions, and each cutting portion having on one side of the bits axis a plurality of teeth alternately facing in opposite directions, on each cutting portion, said blades being pivotally mounted in said bit.

9. A bit of the kind described having a head formed with a plurality of grooves therein, a plurality of reversible blades pivotally mounted in said grooves, and a projection medially disposed on each side of each blade and extending longitudinally thereof and forming a pivot.

10. A bit of the kind described having a head formed with a groove in its lower face, a. blade pivotally mounted in said groove, and a projection medially disposed on each side of the blade and extending longitudinally thereof and forming the pivot of the blade, said groove being of greater size than said blade to permit rocking of said blade through a predetermined angle.

11. A bit of the kind described having a head formed with a plurality of grooves therein terminating at a substantially common center, and a plurality of blades pivotally mounted in said grooves, each of said sitely disposed cutting fluid outlet located between edges, said bit having a adjacent blades.

blades having two oppo- 12. In a rotative bit, a cutter member formed on one side of the axis of the bit with a series of staggered cutting edges facing alternately in opposite directions.

CLYDE E. BANNIBTE 

